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تسجيل مستخدم جديدNew insights into the phase diagram of the copper oxide superconductors from electronic Raman scattering
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Mechanism of unconventional superconductivity is still unknown even if more than 25 years have been passed since the discovery of high-Tc cuprate superconductors by J.G. Bednorz and K. A. Muller. Here, we explore the cuprate phase diagram by electronic Raman spectroscopy and shed light on the superconducting state in hole doped cuprates. Namely, how superconductivity and the critical temperature Tc are impacted by the pseudogap.
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The phase diagram of the cuprate superconductors continues to pose formidable scientific challenges. While these materials are typically viewed as doped Mott insulators, it is well known that they are Fermi liquids at high hole-dopant concentrations.
It was recently demonstrated that at moderate doping, in the pseudogap region of the phase diagram, the charge carriers are also best described as Fermi liquid. Nevertheless, the relationship between the two Fermi-liquid regions and the nature of the strange-metal state at intermediate doping have remained unsolved. Here we show in the case of the model cuprate superconductor HgBa2CuO4+{delta} that the scattering rate measured by the cotangent of the Hall angle remains quadratic in temperature across the pseudogap temperature, upon entering the strange-metal state, and that it is doping-independent below optimal doping. Analysis of the published results for other cuprates reveals that this behavior is universal throughout the entire phase diagram and points to a pervasive Fermi-liquid transport scattering rate. We argue that these observations can be reconciled with other data upon considering the possibility that the pseudogap phenomenon signifies the completion of the gradual, non-uniform localization of one hole per planar CuO2 unit upon cooling.
We present the first comprehensive derivation of the intrinsic electronic phase diagram of the iron-oxypnictide superconductors in the normal state based on the analysis of the electrical resistivity $rho$ of both LaFeAsO$_{1-x}$F$_x$ and SmFeAsO$_{1
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We formulate a theory for the polarization-dependence of the electronic (pair-breaking) Raman response for the recently discovered non-centrosymmetric superconductors in the clean limit at zero temperature. Possible applications include the systems C
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By paying special attention to the fact that the doped holes induce deformation of CuO6 octahedrons (or CuO5 pyramids) in cuprate superconductors, we develop a non-rigid band theory treating doping-induced alterations of energy-band structures in cop
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Universal scaling laws can guide the understanding of new phenomena, and for cuprate high-temperature superconductivity such an early influential relation showed that the critical temperature of superconductivity ($T_c$) correlates with the density o
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